Free Shipping on Prints [USA only]

Free International Shipping options

Sunset on Mars

Martian Sunset

Item# P7997

Select Size & Media:

Availability: Usually ships in 2-3 business days

Product Description

PIA07997 - The robotic
rover Spirit was deployed last month to park and serenely
watch the Sun dip below the distant lip of Gusev
crater. It was a tough job, but some robot had to do it. Now
on Earth a red sunset is caused by two effects -- by blue light being preferentially
scattered out of sunlight by oxygen
and nitrogen
molecules in the atmosphere, and by scattering off a small amount of
impurities like volcanic
dust. (The magnitude of the first effect was computed in one
of Albert Einstein's
most cited papers.)
Although Mars lacks oxygen and nitrogen, it is covered in red dust frequently hoisted
into the atmosphere by fast
but thin winds.
Analyses of images like the above
photograph show that at least some Martian days are capped by
a sunset significantly
longer and redder than typical on Earth. For up to two hours after
twilight, sunlight continued to reflect off Martian
dust high in the atmosphere, casting a diffuse glow. The
result helps atmospheric scientists understand not only the atmosphere
of Mars, but atmospheres across the Solar System,
including our home
Earth.